Refractometric Analysis of Binary Inorganic Solutions

A mathematical equation relating concentration,density and refractivity of binary inorganic solutions was derived,and tested for its validity with aqueous solutions of sodium chloride and of potassium bromide of 7 different concentrations.Refractivity and density of these solutions were determined with the Abbe refractometer and densimeter at 20 ℃.As shown by the comparative study,the values of refractivity (or refractive index) of the binary solutions measured instrumentally were checked very well with the values found by calculation with the equation given,giving maximum deviation at the order of magnitude of 10-4,which is within the precision of the instrument.The proposed equation was valid for calculation of refractive index of binary inorganic solutions of different concentrations.